What Are the Stages of Bedsores?

A bedsore (clinically called a pressure ulcer or pressure injury) is a wound that forms when sustained pressure cuts off blood flow to the skin and underlying tissue. These wounds are entirely preventable with proper medical care. When they reach the most severe stage, they destroy muscle, expose bone, and even become life-threatening.

At the Jacob D. Fuchsberg Law Firm, our experienced New York medical misdiagnosis lawyers represent patients and families harmed when healthcare providers failed to recognize and treat pressure injuries before they became catastrophic. If a loved one developed a Stage 4 bedsore in a hospital or care facility, here is what you need to know and how to proceed.

How Many Stages of Bedsores Are There?

There are four primary stages of bedsores, plus a category called "unstageable". The staging system, recognized by the Agency for Healthcare Research and Quality (AHRQ) and used in clinical settings across the country, classifies wounds by depth of tissue damage:

• Stage 1: Intact skin with persistent redness that does not turn white when pressed.
• Stage 2: Partial skin loss; an open, shallow wound or fluid-filled blister.
• Stage 3: Full-thickness skin loss reaching the fat layer beneath; a crater-like wound.
• Stage 4: Full-thickness tissue loss exposing bone, tendon, or muscle.
• Unstageable: Wound covered by dead tissue; depth cannot be determined without removal of that tissue.

The earlier stages respond well to prompt repositioning and wound care. Stage 3 and Stage 4 are medical emergencies. According to the Centers for Disease Control and Prevention (CDC), approximately 11% of nursing home residents develop pressure ulcers each year, and advanced-stage wounds carry a significantly elevated risk of fatal complications.

The Beginning Stages of Bedsores: Stages 1-3 at a Glance

The first three stages represent a progression that, with competent medical care, should never reach Stage 4.

Stage 1: Reddened Skin

Skin remains intact. The affected area appears persistently red on lighter skin tones or darker and discolored on darker skin tones. The site may feel warmer or cooler than surrounding tissue, and may be tender. Stage 1 resolves with repositioning and basic skin protection.

Stage 2: Partial Skin Loss

The outer skin layer and part of the second layer are damaged. The wound appears to be a shallow open sore or blister with a pink-red wound bed. Moisture-retentive dressings and pressure relief are typically enough at this stage.

Stage 3: Full-Thickness Wound

Damage reaches the fat layer beneath the skin. The wound becomes a deep, crater-like opening. Tunneling (a hidden channel of damage beneath seemingly intact skin) may be present. Infection risk rises sharply, and a medical specialist must be involved.

A person should never reach Stage 4 under attentive medical supervision. Stage 3 to Stage 4 progression reflects a breakdown in the standard of care, not an inevitable outcome of illness.

Stage 4 Bedsores: The Most Severe Level

Stage 4 is the deepest documented level of tissue destruction. At this point, the wound exposes muscle, bone, or supporting structures such as tendons or joint capsules. Dead tissue (eschar) is typically present. The surrounding skin is often black or necrotic.

What a Stage 4 Bedsore Looks Like

Stage 4 wounds are unmistakable. Common characteristics include:

• Black or darkened wound edges from tissue death (necrosis).
• Exposed bone, tendon, or muscle visible at the base of the wound.
• Tunneling or undermining: the wound extends beneath the surrounding skin.
• Foul odor from necrotic tissue or active infection.
• Thick or discolored drainage from the wound site.

Patients at Stage 4 often report little or no pain in the wound itself. The nerve endings in that tissue have been destroyed.

Life-Threatening Complications

Stage 4 bedsores go far beyond skin damage. Left untreated or mismanaged, they lead to systemic, often fatal conditions:

• Sepsis: A body-wide infection response that can cause organ failure and death.
• Osteomyelitis: Bone infection that may require surgical removal or amputation.
• Cellulitis: Spreading bacterial infection of the surrounding skin.
• Bacteremia: Bacteria in the bloodstream.
• Endocarditis: Infection of the heart's inner lining in severe sepsis cases.

Each complication carries its own mortality risk. When sepsis develops from a Stage 4 bedsore, the situation can become fatal within days without aggressive hospital-level intervention.

What Causes a Bedsore to Reach Stage 4

Stage 4 does not develop overnight. It results from documented, preventable failures in care:

• Failure to reposition an immobile patient at least every two hours, which is a standard of care requirement under federal nursing home regulations;
• Lack of a pressure-redistributing mattress or cushion provided to patients flagged as high-risk;
• Wound assessments documented but not acted on: progression noted in the chart, yet treatment not escalated;
• Inadequate nutrition and hydration: the body cannot repair tissue without protein, zinc, and fluids;
• Delayed referral to a wound care physician despite visible deterioration over days or weeks;
• Discharge without wound care instructions: a misdiagnosis scenario where an advanced wound goes home without a follow-up plan.

When a hospital or nursing facility knew about a wound and failed to act, that failure can form the basis of a medical malpractice claim.

Stage 4 Bedsore Treatment

Treatment at Stage 4 requires a full interdisciplinary team and typically includes:

• Surgical debridement: Removal of dead, infected, and damaged tissue.
• Negative pressure wound therapy (NPWT): A vacuum-sealed dressing system that promotes wound healing.
• Skin grafting: Healthy skin transplanted to cover the wound in severe cases.
• IV antibiotics: To treat or prevent systemic infection.
• Nutritional support: High-protein intake or supplemental feeding to rebuild tissue.
• Ongoing wound monitoring by a certified wound care nurse.

Recovery, when possible at all, takes months. Many patients do not survive the infections that accompany Stage 4 wounds.

When a Stage 4 Bedsore Becomes a Legal Case in New York

Not every bedsore results from malpractice. However, a Stage 4 pressure injury, particularly one that developed under inpatient or residential care, almost always reflects a failure to follow the standard of care. A medical malpractice attorney will examine:

• Was the patient assessed as high-risk for pressure injuries upon admission?
• Were repositioning schedules documented and carried out?
• Did staff document the wound's progression without escalating treatment?
• Was a wound care physician consulted before Stage 4 was reached?
• Were family concerns about the wound documented and addressed?

In New York, medical malpractice claims are governed by CPLR § 214-a, which sets a general statute of limitations of 2.5 years from the date of the alleged malpractice. Exceptions exist for continuous treatment and certain discovery situations, but waiting too long puts a valid claim at risk.